1. Field
This disclosure relates generally to semiconductors, and more specifically, to upset events caused by energetic particles in semiconductors.
2. Related Art
As the demand for smaller devices continues, the devices that make up integrated circuits continue to shrink. As the size of the semiconductor devices decreases, the number of structures susceptible to errors caused by energetic particles similarly increases. This is generally most significant for volatile memories but other circuits can be impacted as well. Soft errors can occur, for example, when external energy, such as energy due to alpha particle bombardment, is imparted onto the circuit, causing bit values in volatile memory, logic registers, and other devices, to change to erroneous values. Latch-up can also be induced in circuits by energetic particles. Latch-up can be destructive or non-destructive. Whether the event is destructive or non-destructive, the event may be called an upset event.
Mitigation techniques can be employed to minimize the impact of an energetic particle strike. One technique is a voting arrangement which requires redundancy and the ability to perform the vote. Error correction is another approach which requires another type of redundancy and may still be inadequate, especially if the upset event is destructive. Another approach is simply to detect that an energetic particle that will typically cause an upset event has struck the circuit. This may be all that is desired due to the high cost of the space required to mitigate the impact. Further, detection of the upset event is likely to be needed even if there is a need to mitigate the impact of an upset event.
Accordingly there is a need to provide further improvement in obtaining upset event information.